AN UNPRECEDENTED intervention into the migrant crisis in the Aegean Sea will be expanded and joined by a British warship.
Prime Minister David Cameron was set to announce the move overnight as desperate European leaders met in Brussels to try to stop another wave of refugees crossing to the EU from Turkey.
Leaders at the summit are pinning their hopes on a deal with Turkey to prevent more people attempting the hazardous journey to Europe.
Turkish Prime Minister Ahmet Davutoglu, who is attending the summit, has promised to take back all non-Syrians who arrive in Greece.
However, human rights groups say the EU is shirking its humanitarian responsibilities by using Turkey as its border guard.
"Many refugees still live in terrible conditions, some have been deported back to Syria and security forces have even shot at Syrians trying to cross the border," said Amnesty International's deputy director for Europe and Central Asia, Gauri van Gulik.
The EU has offered Turkey $5.7 billion and the prospect of an easy visa regime for Turkish visitors in return for action to stop the estimated 2.6 million Syrian refugees from leaving Turkish shores.
This includes stepping up police and coastguard operations to stop the people smugglers who are still ferrying nearly 2000 people a day to Greece.
Some of the refugees will be sent back to Turkey by NATO, whose patrols around the Aegean Sea are intercepting migrants trying to reach Greece.
Mr Cameron was to announce that those patrols would be joined by a British warship.
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